Cylinders
Every cylinder connects to any Dr. Joel Kaplan pump system with a quick-disconnect fitting. Choose your size below, or measure first for a precise fit.
Measure Once, Fit Right the First Time
Cylinders are sized by circumference, not guesswork. Take a quick measurement and match it to the chart below, over 80% of men fall into our Medium size. If you land between sizes or aren't sure, every order includes a free size exchange within 30 days (you only cover return shipping).
Circumference Size Cylinder Diameter
Up to 5" Small 1.75" 5.10" – 5.50" Medium 2.00" 5.51" – 6.25" Large 2.25" 6.26" – 8.00" X-Large 2.50"
Medium (2.00") fits over 80% of men. Still unsure? Call us at 1-800-354-3944 — Mon–Fri 7:30AM–5PM PST.
Standard Cylinders
Our original 9" cylinder line. Quick-disconnect fitting works with every Dr. Joel Kaplan pump.
Erection Cylinder
$69.00
1.75" Small
2.00" Medium
2.25" Large
2.50" X-Large
Shop Sizes
2nd Expansion Cylinder
$89.00
2.75" Small
3.00" Medium
3.25" Large
3.50" X-Large
Shop Sizes
Extra-Long Cylinders — 12"
Same cylinder line at 12" for pump systems requiring additional length. Available in both diameter ranges below.
Erection Cylinder — 12" Extra Long
$99.00
1.75" Small
2.00" Medium
2.25" Large
2.50" X-Large
Shop Sizes
2nd Expansion Cylinder — 12" Extra Long
$129.00
2.75" Small
3.00" Medium
3.25" Large
3.50" X-Large
Shop Sizes
Head Attachment
A seamless, one-piece attachment that connects to any Dr. Joel Kaplan pump system with the same quick-disconnect fitting as our cylinders.
$59.00
One Size — fits up to 5.25" circumference
View Details
How Cylinders Work With Your Pump
1. Connect
Attach any cylinder to any Dr. Joel Kaplan pump with the quick-disconnect fitting.
2. Create the Seal
The cylinder forms an airtight seal so the pump can draw a controlled vacuum.
3. Achieve a Fuller Erection
Increased blood flow produces a firmer, more complete erection for intercourse.
All cylinders shown are compatible with every Dr. Joel Kaplan pump system.
Not Sure Which Size?
Every cylinder ships with a 30-day free size exchange — you only pay return shipping. Measure first, order with confidence.
View Size Chart
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